Several methods of inoculating milk to manufacture cheese are known to the art. In the most common method (referred to herein as the "traditional" system), an inoculum having about 10.sup.9 CFU/g is added to a growth medium comprising about 7% to 12% solids to produce an inoculated medium having about 10.sup.5 CFU/g. The inoculated medium is then "grown" for about 16-20 hours at a temperature of about 20-25.degree. C. to produce a starter culture having at least about 10.sup.9 CFU/g. That starter culture is then added to milk to produce the final product..sup.1 FNT .sup.1/ In an alternative method (referred to herein as the "direct vat inoculum" method), an inoculum having about 10.sup.11 CFU/g is added directly to milk to produce the cheese.
One disadvantage of the traditional method is that it requires growth periods of 16-20 hours to produce the starter culture. This obviously means that comparably long times are required to process each batch of starter, and that the costs of production for each batch will be correspondingly high. Also, due to the fact that the growth medium must be capable of supporting bacterial growth from the initial level of 10.sup.5 CFU/g to the ending level of 10.sup.9 CFU/g, the medium must include a variety of costly components such as phosphates, minerals, yeast extracts, etc. Total solids levels for such media typically are in the range of 7% to 12% or more.
A need therefore exists for a method of preparing starter cultures that reduces the time and cost of materials needed to process each batch, including media costs, and accordingly reduces production costs. The present invention addresses this need.